News

A new piece in the puzzle of neuronal locomotion control

September 2018. Scientists deciphered the function of an important class of motor neurons in a model species.

Many aspects of the neuronal control of basic behaviours are not yet understood. One big question is for example how the highly complex locomotion circuits of humans and other vertebrates operate in detail. As movements are regulated by neuronal circuits that share similar properties in a wide variety of species, including humans, scientists can use other species as models. Vertebrates even share similar principles with invertebrates despite their different locomotion and anatomy of neural circuits. The relative simplicity of invertebrate nervous systems has helped to develop concepts that guide our understanding of how more complex neuronal networks operate.

The small nematode worm C. elegans is a particularly useful invertebrate model for this area of research as all its 302 neurons are known and a wiring diagramme of its neural circuits is available. A team of scientists led by Alexander Gottschalk from the Buchmann Institute for Molecular Life Sciences at Goethe University Frankfurt has investigated circuit activity in C. elegans to fill an important gap in the understanding of how the worm's undulatory wave-like movement is controlled. Using optogenetic, behavioural and imaging analyses, they studied a class of motor neurons whose function was not known. They found that these “AS cholinergic motor neurons” generate asymmetric muscle activation, enabling navigation and contribute to coordination of dorso-ventral undulation as well as anterio-posterior bending wave propagation. More ...